I've always thought that, from a perspective of developing a realistic game, you wouldn't only want a "wetness" modifier to clothing, but you'd also want to have all sorts of conditions of being soiled somehow. So, for instance, if you're cut and are bleeding, the clothing would become soiled with blood. There might be ways for clothes to pick up dirt or mud. This would create an element to the game where you wouldn't only have to dry wet clothes, but would have to wash ones with other sorts of conditions. On top of that, metals would have problems like rust if they weren't taken care of well enough.
While this would not fit the style of most games, to me, UrW has always been a slow-going game, where these types of requirements just add to the sense of "being there", and give you more to do as a player.
To the extent that not only your clothes and metals can get conditioned, possibly your character could also get dirty; and this would be a condition for taking a bath.